\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Study 1 Summary Statistics \label{immigrationcanvassdemos}}
\begin{tabular}{l*{1}{cc}}
\hline\hline
                    &\multicolumn{2}{c}{}     \\
                    &        mean&          sd\\
\hline
Age                 &       24.26&        4.86\\
Female              &        0.74&        0.45\\
Latino              &        0.30&        0.47\\
Immigrant           &        0.22&        0.42\\
Very Liberal        &        0.48&        0.51\\
Liberal             &        0.22&        0.42\\
Moderate            &        0.30&        0.47\\
Conservative        &        0.00&        0.00\\
Very Conservative   &        0.00&        0.00\\
Prior Campaign Experience&        0.57&        0.51\\
Prior Perspective-Getting Experience&        0.30&        0.47\\
\hline
Observations        &          23&            \\
\hline\hline
\end{tabular}
\end{table}
